U.S. patent number 5,660,370 [Application Number 08/612,324] was granted by the patent office on 1997-08-26 for valve with flexible sheet member and two port non-flexing backer member.
This patent grant is currently assigned to Integrated Fludics, Inc.. Invention is credited to Milo E. Webster.
United States Patent |
5,660,370 |
Webster |
August 26, 1997 |
**Please see images for:
( Certificate of Correction ) ** |
Valve with flexible sheet member and two port non-flexing backer
member
Abstract
A valve has a flexible sheet member which moves toward and away
from a flat, non-flexing sheet member to cover and open two holes
in the nonflexing sheet member to block or permit fluid flow
between passageways in a second valve body portion member. The
flexible sheet member is extendible into a recess formed in a first
valve body portion member above the two holes so that fluid flows
from one passageway through a chamber formed between the
non-flexing sheet member surface and the faring surface of the
flexible sheet member. The plunger head of a solenoid forces the
flexible sheet member into contact with the non-flexing sheet
member and when excited causes the plunger head to be moved out of
contact with the flexible sheet member allowing the flexible sheet
member to uncover the holes in the nonflexing sheet member. Vacuum
is present at the valve site and draws the flexible sheet member
away from the non-flexing sheet member substantially immediately as
the plunger head is withdrawn from contact with the flexible sheet
member. The solenoid is releasably engageable with a solenoid
receiving opening in the first valve body portion at the valve
site.
Inventors: |
Webster; Milo E. (Yarmouth
Port, MA) |
Assignee: |
Integrated Fludics, Inc.
(Plainville, CT)
|
Family
ID: |
24452686 |
Appl.
No.: |
08/612,324 |
Filed: |
March 7, 1996 |
Current U.S.
Class: |
251/129.17;
137/884; 137/885; 251/331; 251/61.1 |
Current CPC
Class: |
F16K
7/17 (20130101); Y10T 137/87893 (20150401); Y10T
137/87885 (20150401) |
Current International
Class: |
F16K
7/12 (20060101); F16K 7/17 (20060101); F16K
007/12 (); F16K 031/06 () |
Field of
Search: |
;251/61.1,331,129.17
;137/884,885 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Lee; Kevin
Attorney, Agent or Firm: McCormick, Paulding & Huber
Claims
The invention claimed:
1. A valve comprising:
a first valve body portion member having a substantially flat
surface;
a second valve body portion member having a substantially flat
surface;
a flexible sheet member positioned between said flat surfaces of
said first and said second valve body portion members;
a non-flexing sheet member positioned between said flexible sheet
member and said flat surface of said second valve body portion
member;
a recess portion in the first valve body portion member formed in
the flat surface and into which a portion of said flexible sheet
member is extendible;
at least two ports extending through said non-flexing sheet member
at spaced locations and disposed opposite said recess portion in
the first valve body portion member;
at least two fluid passageways formed in the second valve body
portion member and in respective registration one-for-one with said
at least two ports in said non-flexing sheet member;
means for flexing said flexible sheet member toward and away from
said non-flexing sheet member whereby when said flexible sheet
member is flexed against the non-flexing sheet member, said
flexible sheet member covering and sealing at least one of said
ports in said non-flexing sheet member to block fluid communication
between said two fluid passageways formed in the second valve body
portion member, and when said flexible sheet member is flexed away
from the non-flexing sheet member said two ports in said
non-flexing sheet member are uncovered to permit fluid
communication between said two fluid passageways formed in said
second valve body portion member.
2. A valve as defined in claim 1 further comprising said flexible
sheet member being made of a polyethylene film material and said
non-flexing sheet member being made of a polyethylene film
material.
3. A valve as defined in claim 1 further comprising said flexible
sheet member having a thickness in the range of 0.0005 inches and
said non-flexing sheet member having a thickness in the range of
0.003 to 0.015 inches.
4. A valve as defined in claim 1 wherein each of said at least two
ports has a diameter in the range of 0.031 inches and are spaced
from one another in the range of 0.062 inches on center.
5. A valve as defined in claim 1 wherein said first valve body
portion member and said second valve body portion member are made
of a non-corrosive, relatively inert material.
6. A valve as defined in claim 5 wherein said non-corrosive,
relatively inert material is an acrylic material.
7. A valve as defined in claim 1 wherein said means for flexing
said flexible sheet member toward and away from said non-flexing
sheet member comprises a solenoid, said solenoid having a plunger
head movable by spring pressure toward and away from non-flexing
sheet member, said plunger head contacting and pushing against said
flexible sheet member when in an unenergized state whereby at least
one of said ports is covered and sealed and whereby said plunger
head is retracted away from said flexible sheet member when in an
energized state to allow said flexible sheet member to be extended
into said recess portion in said first valve body portion member by
pressure developed by fluid in said fluid passageways to permit
fluid communication between said two fluid passageways.
8. A valve as defined in claim I wherein said means for flexing
said flexible sheet member toward and away from said non-flexing
sheet member comprises a solenoid, said solenoid having a plunger
head movable toward and away from non-flexing sheet member, said
plunger head contacting and pushing against said flexible sheet
member when in an unenergized state whereby said at least one of
said ports is covered and sealed;
a source of vacuum coupled to said first body portion to provide a
vacuum between said flexible sheet member and said recess portion,
and
whereby said plunger head is retracted away from said flexible
sheet member when in an energized state to allow said flexible
sheet member to be extended into said recess portion in said first
valve body portion member by said vacuum attracting said flexible
sheet member into said recess portion whereby fluid in said fluid
passageways is in fluid communication between said two fluid
passageways.
9. A valve as defined in claim 8 further comprising said solenoid
having a lower portion including an outer peripheral
circumferential groove, an O-ring received within said groove, a
solenoid receiving opening in said first valve body portion for
axially receiving said solenoid within said first body portion at a
valve site such that said plunger head is in axial alignment with
said two holes in said non-flexing sheet member, said solenoid
receiving opening having an inner peripheral surface detent for
receiving said O-ring and said solenoid to provide an airtight seal
between said flexible sheet member and said solenoid, said inner
peripheral surface detent being axially positioned toward said
flexible sheet member whereby said solenoid is biased toward said
valve site when said solenoid is inserted or "popped in" said
solenoid receiving opening.
10. A valve as defined in claim 9 wherein said solenoid is
removable from said first valve body portion member by applying an
axial force to said solenoid in a direction away from said valve
site to overcome the biasing force holding said solenoid in said
solenoid receiving opening.
Description
BACKGROUND OF THE INVENTION
The present invention relates generally to valves, particularly
microvalves, and more specifically relates to a valve that employs
a very thin flexible sheet member to seal against at least one of
two ports in a non-flexing, substantially flat backer member to
provide or block fluid communication between passageways
terminating at the ports at the valve site. The valve is
particularly suited for use in valve matrixes or arrays of the
general type used in flow networks for handling various types of
fluids or liquids.
In accordance with an earlier invention covered by my U.S. Pat. No.
4,304,257, I disclosed a valve that includes a body member that has
a firm and stable support surface and a flexible sheet member that
has a surface for conforming and mating with the surface of the
valve body member. There are at least two fluid flow channels in
the surface of the body member separated from each other by a land
portion. A mechanical actuator is employed to flex the sheet member
between a first position in which a surface of the sheet is in
mating and sealing engagement with the surface of the body member
to block flow between the two channels and a second position in
which the sheet surface is spaced from the first position to allow
fluid flow across the land surface between the two flow
channels.
The flexible sheet member is a manifold diaphragm sheet made of
polyurethane or silicone and of sufficient thickness such that
heads formed on the ends of stems of the mechanical actuators can
be embedded in the sheet. This requires the sheet to have
substantial thickness. Because the sheet is an elastomer, were it
able somehow to be made thinner, it could be gas pervious which is
undesirable.
The actuators are solenoid operated which are not only bulky but
heavy and employ substantial power for actuation. This is somewhat
limiting to the function of the valve, particularly when many
similar valves are assembled together in a manifold environment.
The actuators also require extremely sensitive adjustment.
In accordance with my earlier invention, the flexible sheet is
pulled physically downwardly into an aperture so that the surface
of the sheet which is engageable with the firm and stable support
surface is withdrawn from that surface plating two or more fluid
passageways in communication. The flexure is all in one direction,
that is, downwardly from the horizontal and returned to the
horizontal.
Also in accordance with my earlier invention, when the flexible
sheet is pulled away from the support surface, it exposes the land
which is coincident with the support surface. A space is created,
which when filled with a fluid flowing from one channel or
passageway, can then flow out the second or additional passageways
in communication with the space. An improvement over my earlier
patent allows flow across the land to be channeled or directed to
permit such flow to take place substantially immediately upon the
flexible sheet surface being withdrawn from the support surface
rather than waiting for the space to become filled or substantially
filled.
A further improvement to my earlier patent reduces the flexing of
the flexible sheet to avoid undue stress concentration at any one
point or points and secondly, to reduce the tendency of the sheet
to become stressed beyond its yieldpoint.
The improvements to my earlier '257 patent are disclosed in my U.S.
Pat. Nos. 4,848,722, 4,852,851 and 4,858,883 assigned to the same
assignee as the present invention. In the above patents, a valve
with a flexible sheet member and capable of solenoid actuation
using fluid or vacuum is disclosed that has at least one track in
contact with the mylar or flexible sheet wherein the surface is
broken with a concave void or a "canal". In the valve described in
the patents, the flexible sheet member is deformed or stretched at
the valve site as it is flexed to engage and disengage against the
curved surface of the valve site to provide the desired
communication or block the flow of fluid between the passageways at
the valve site. Although the wear is improved over my earlier
patent with the above design, the flexible sheet member at the
valve site still flexes approximately 50% from an at rest position
and is still required to engage or seal against the ridges or edges
of the channel ends or openings to provide the desired
communication or block the flow of fluid between the passageways at
the valve site.
A further disadvantage of the valve of the above patents is that
the valve site cannot be made fail-safe in the event of a loss of
pressure or vacuum to seal the flexible sheet against the valve
site surface thus allowing fluid to communicate between
passageways.
Accordingly it is a general aim of the present invention to provide
a further improved valve with a flexible sheet member that
substantially reduces the distance the sheet member must be flexed
to provide the desired communication or block the flow of fluid
between the passageways at the valve site.
It is a further aim in one embodiment of the present invention to
provide an improved valve with a flexible sheet member that seals
against at least one of two spaced holes or ports in a
substantially flat, non-flexing surface and which holes or ports
are in registration with respective passageways at the valve site
to provide the desired communication or block the flow of fluid
between the passageways at the valve site.
It is a still further aim of the present invention to provide an
improved valve with flexible sheet member that is capable of
actuation by means of a solenoid which seals the valve when at rest
with a spring or mechanical hold down and a constant vacuum which
opens the valve when the solenoid is excited.
It is yet a further aim to provide an improved valve with a
flexible sheet member that is capable of actuation by means of
pressure and vacuum through a three way valve which may be either
built in or remote from the valve.
It is a yet further aim of the present invention to provide a valve
array that is capable of a high density arrangement with mechanical
solenoid operation to form a matrix of valve sites.
It is a still further aim of the present invention to provide an
improved flow through valve with a flexible sheet member.
SUMMARY OF THE INVENTION
In accordance with the present invention, a valve having a flexible
sheet member covers and uncovers two holes in a non-flexing sheet
member at a valve site. The valve has a first valve body portion
member with a recess into which the flexible sheet member can be
extended to uncover the two holes in the non-flexing sheet member
so that passageways in registration with the respective holes in
the non-flexing sheet member and formed in a second valve body
portion member are in fluid communication with one another when the
flexible sheet member is drawn into the recess and fluid
communication is blocked when the flexible sheet member is forced
into contact with the non-flexing sheet member.
In a further aspect of the invention, a solenoid has a plunger head
which moves toward and away from the flexible sheet member to force
the flexible sheet member to cover at least one of the two holes in
the non-flexing sheet member to block fluid communication and when
the solenoid is excited to withdraw the plunger head to allow the
flexible sheet member to move away from and uncover the holes in
the non-flexing sheet member to allow fluid communication.
In a further aspect of the invention, the valve site is provided
with a constant vacuum to draw the flexible sheet member
substantially immediately away from the holes when the solenoid is
exalted. This feature eliminates the need for a pressurized source
or pressure pump to be involved with the operation of the valve
site.
BRIEF DESCRIPTION OF THE DRAWINGS
Other features and advantages of the present invention will become
readily apparent from the following written description and
drawings wherein:
FIG. 1 is a cross-sectional enlarged view of a shut-off valve body
embodying the valve and flexible sheet member of the present
invention showing the valve in its open condition to provide the
desired communication between passageways at the valve site;
FIG. 2 is a cross-sectional enlarged view of the shut-off valve
body embodying the valve and flexible sheet member of FIG. 1
showing the valve in its shut-off condition to block the flow of
fluid between passageways at the valve site;
FIG. 3 is a cross-sectional view of the valve and flexible sheet
member of the present invention showing in enlarged view an
adhesive layer between the non-flexible Mylar sheet and the upper
surface of the lower valve body member;
FIG. 4 is an exploded perspective enlarged view of a typical
construction of the valve body of FIGS. 1 and 2;
FIG. 5 is a cross-sectional view of a typical flow through valve
body embodying the valve and flexible sheet member of the present
invention;
FIG. 6 is an exploded perspective enlarged view of the flow through
valve body illustrated in FIG. 5;
FIG. 7 is a cross-sectional view of a flow regulating shut-off
valve body embodying the valve and flexible sheet member of the
present invention;
FIG. 8 is a cross-sectional view of an alternate embodiment of the
shutoff valve body embodying the valve and flexible sheet member
with multiport backer having three ports at the valve site;
FIG. 9 is a partial top view of the non-flexing multi-port backer
member of the valve of FIG. 8 showing the ports at the valve
site;
FIG. 10 is an exploded, enlarged view showing the non-flexing
multiport backer and lower valve body member of the shut-off valve
body of FIGS. 8 and 9;
FIG. 11 is an enlarged partial cross-sectional view of one
embodiment of a solenoid actuated valve at a valve site.
FIG. 12 is an enlarged partial cross-sectional view of an alternate
embodiment of a solenoid actuated valve at a valve site;
FIG. 13 is an enlarged partial cross-sectional view of a valve
embodying the multi-port backer member and thin flexible sheet
member of the present invention wherein the valve is operated
remotely utilizing vacuum and pressure;
FIG. 14 is an exploded perspective enlarged view of a valve array
embodying the valve and flexible sheet member with two port backer
and solenoid actuator embodying the present invention.
WRITTEN DESCRIPTION OF PREFERRED EMBODIMENTS
Turning now to the drawings and considering the invention in
further detail, the basic valve body embodying the present
invention is shown in an enlarged cross-sectional view in Figs, 1
and 2 and is generally designated 10. A number of valve bodies may
be arranged as an integral valve array or valve matrix as explained
in further detail below in connection with the discussion of FIG.
5. The valve body 10 includes a first valve body portion member 12
and a second valve body portion member 14 which may be referred to
as the upper and lower valve body members, respectively. The valve
body members may be made of acrylic material or any other
noncorrosive, relatively inert, material which may be machined or
molded.
A plurality of passageways 16,17 through which fluid may flow are
formed in the lower body portion member 14. The passageways may be
holes, grooves, flow through channels or any convenient fluid
conduit form generally well known to those in the art. Reference
may be made to any of the above mentioned patents for further
information and explanation and the disclosures of which patent
references are incorporated herein by reference. As will be
apparent connecting tubes may lead to and from the passageways to
fluid reservoirs and/or equipment.
A flexible sheet member 18 which may be a sheet of polyethylene
film of the type sold by Dupont under the tradename Mylar, or other
suitable material that flexes is placed at an interface generally
designated 20 between the upper and lower valve body portion
members with the flexible sheet member positioned adjacent the
downwardly facing surface 22 of the upper valve body portion member
12. An extra non-flexing layer or backer member 24 made of Mylar or
other suitable material for example, metal "shim stock", is located
between the flexible sheet member 18 and the upwardly facing
surface 32 of the lower valve body portion member 14. The upper and
lower valve body portion members together with the flexible sheet
member 18 and non-flexing backer member 24 therebetween form a
sandwich. The upper valve body portion member 12 may be bolted,
screwed, bonded or otherwise attached using other well known means
to the lower valve body portion member 14 to form the sandwiched
structure. As illustrated, two valve body portion members are shown
but it will be recognized there can be any number of valve body
portions sandwiched together. Alternately the valve body members,
non-flexing sheet and flexible sheet may be adhesively held to one
another or may be molecularly bonded.
The upper valve body member 12 has a recess portion 26 at the
location of the valve site and is defined by a concave surface 28
formed in the surface 22 of the upper valve body portion member and
the upper surface 30 of the flexible sheet member 18 which faces
the surface 22. In the illustrated embodiments, passageways 16,17
terminate in orifices or holes 16a,17a in the upper surface 32 of
the lower valve body 14 at the valve site. The orifices 16a,17a are
spaced apart and the non-flexing backer member 24 has corresponding
ports or holes 34,35 therethrough in registry with the orifices
16a,17a. When the flexible sheet 18 is flexed into the recess
portion 26, the valve is in its open flow condition and provides
fluid communication between the passageways 16,17. When the
flexible sheet 18 is forced into contact with the upper flat
surface 36 of the non-flexing Mylar backer member 24, the bottom
surface 39 of the flexible sheet covers or seals against the flat
surface 36 and seals the holes 34,35 to shut-off fluid
communication between the passageways 16,17. A control passageway
42 extends between the surface 28 of the recess portion 26 and is
connected by an appropriate conduit 46 and source of pressure
and/or vacuum 48 shown in phantom. In the basic illustration of the
present invention, the valve is closed when pressure is exerted
against the upper surface of the flexible sheet member at the valve
site and is open when a vacuum is applied to the flexible sheet
member at the valve site.
As illustrated in a preferred embodiment in FIG. 4, the extra layer
(in contrast to prior art valves where the flexible sheet member
seals against the edges of a groove, hole or canal) of non-flexing
Mylar backer member 24 is thicker than the flexible sheet member 18
and may be approximately 0.003 to 0.015 inches thick while the
flexible sheet 18 may be 0.0005 inches thick to provide a ratio of
6:1. Obviously other dimensions may be used dependent on material
and other design considerations. For purposes of a continued
example of one preferred embodiment, the non-flexing Mylar backer
member 24 has two holes or ports punched therethrough each having
an approximate diameter of 0.031 inches on 0.062 inch centers. As
described above, the holes 34,35 provide a conduit to the next
adjacent layer, in this example, the lower valve body portion
member 14 which may have configurations (tracks, canals, grooves,
channels and so forth) similar to those disclosed in the above
referenced patents. The non-flexing Mylar backer member 24 may be
adhesively adhered to the lower valve body portion 14 containing
the tracks, grooves, etc. by a thin adhesive layer 50 as
illustrated in FIG. 3, and since the non-flexing Mylar backer
member 24 has only two ports or holes at each valve site, there are
no tracks below the surface of the block, the potential for
"cross-talk" that exists in the three-way valves of my previous
patents is eliminated.
A further benefit of the present invention is that the sealing is
Mylar-to-Mylar surface with the sealing sites only being holes and
not track edges or grooves as in my previous patents. Furthermore,
the surface finish of Mylar film is far superior to a machined and
polished surface.
A further benefit and advantage of the valve design of the present
invention is the non-flexing Mylar backer member 24 can be
dedicated to only holes and tracks, grooves, canals, etc., and
therefore the manufacturing of the part can be by any number of
mass production methods including injection molding, stamping,
casting, chemically etching, etc. as known in the art. The
substantial cost reduction that may be realized using mass
production techniques may provide for designs which lend themselves
to being disposable as a package or component which is particularly
desirable in diagnostic applications.
It is also possible to laminate into the valve structure various
membranes that serve as a diffusion medium for gases that may
emanate from biological or non- biological fluids or serve as a
transfer or exchange medium (osmotic) between two liquids or gases
or between a liquid and a gas.
Turning to FIG. 4, the valve body shown in FIGS. 1 and 2 embodying
the valve and flexible sheet member of the present invention is
illustrated in an exploded perspective enlarged view wherein the
upper valve body portion member 12, thin flexible Mylar sheet 18
and non-flexible Mylar backer member 24 are substantially as shown
and described above. The upper surface 32 of the lower valve body
portion member 14 is adjacent to the lower surface 38 of the
non-flexing Mylar body member 24. The upper surface, as shown, has
grooves or tracks, also known as canals, 16,17 in the surface 32 of
the lower valve body 14. The lower surface 38 seals the grooves or
tracks 16,17 when the valve body is assembled. As clearly shown in
FIG. 4, the tracks or grooves 16,17 are not sealed by the thin,
flexible Mylar sheet 18.
Turning now to FIGS. 5 and 6, the valve and flexible sheet member
with a two port non-flexing backer member embodying the present
invention is illustrated therein in a "flow through" configuration.
The "flow through" valve is designated generally 52 and appears
very similar to the valve described above having an upper valve
body portion member 12, thin flexible Mylar sheet 18 and
non-flexible Mylar backer member 24. In FIGS. 5 and 6, the lower
valve body portion member 54 has an upper surface 56 in abutting
contact with the lower surface 38 of the backer member 24. The
surface 56 of the valve includes a groove 58 in registration and in
communication with the hole or port 35 in the backer member 24. As
shown for illustrative purposes, the groove 58 has one end 62 in
communication with a passageway 60. The surface 56 also has a
channel 64 having one end 66 in registration and in communication
with the hole or port 34 in the backer member 24. The opposite end
68 is in communication with a passageway 70 terminating in the
lower surface 72 of the valve body portion member 54. When the
structure is assembled and the valve is in its shut-off condition,
that is, the holes 34,35 are sealed or covered by the surface 39 of
the thin flexible Mylar sheet member 18 at the valve site, fluid
communication is established on a flow through basis between the
passageway 60, through the groove 58 and exiting the outlet 59
which outlet 59 is typically coupled to a hose, tube or other fluid
connector. At some time, for example during the course of an
analysis, it may be desired to add a different fluid or reagent to
the flow-through fluid by operating the valve so that the second
fluid can be added through the passageway 70, through channel 64,
through hole 34, through the chamber formed between the surface 39
of the flexible sheet member 18 and the surface 36 of the backer
member 24 at the valve site when the valve is operated, back
through the hole 35 into the groove 58 to be mixed with the
flow-through fluid entering the passageway 60. It will be
appreciated that numerous configurations can be accommodated with
the valve design of the present invention.
An alternate embodiment of the present invention is illustrated in
FIG. 7 and is generally designated 80. The valve body is similar to
the valve body described in FIGS. 1 and 2 except that the
non-flexing backer member designated 82 includes an opening 84 and
86 at the valve site wherein the diameter of the opening 84 is
smaller than the opening 86 to restrict or regulate the fluid flow
through the valve when the valve is operated. The openings 84, 86
are in registry with the canals or channels 16,17 respectively in
the lower valve body member 14 as described in connection with the
description of FIGS. 1 and 2 above. Since fluid only flows through
the valve site when the valve is operated, the flow can be
regulated or restricted by selectively choosing the diameter of the
opening 84. This feature is particularly useful when the valve is
used as a mixing valve to supply a predetermined volume of fluid as
required to obtain a given concentration. It will be recognized by
those skilled in the art that the fluid flow restriction is
determined from the diameter of the opening, fluid pressure
supplied in the channel and the diameter of the second opening at
the valve site.
Turning now to FIGS. 8,9 and 10, a multi-port valve body embodying
the present invention is illustrated therein and is generally
designated 100. The valve body 100 is similar to the valve body
illustrated and described above. The valve body 100 includes an
upper valve body portion member 102, a lower valve body portion
member 104, a non-flexing backer member 106 and very thin flexible
sheet member 108. The flexible sheet member 108 is sandwiched
between the lower surface 110 of the upper valve body portion
member 102 and the upper surface of the non-flexing backer member
106. The lower surface 118 of the non-flexing backer member 106 is
adjacent to the upper surface 120 of the lower valve body member
104 and is used to seal channels or grooves in the surface 120 to
form the desired passageways which terminate at the ports in the
non-flexing backer member 106. As best shown in FIG. 10, the
surface 120 of the lower valve body portion member 104 has a first
groove 122 terminating at an end 124 which end is in registration
with a port 126 in the non-flexing backer member when the valve is
assembled. A second groove 128 terminates at an end 130 which end
is in registration with the port 132 in the non-flexing backer
member 106 when the valve is assembled. For purposes of example, a
passageway 134 extends through the lower valve body member 104
terminating at an end 136 which end is in registration with the
port 138 in the nonflexing backer member 106 when the valve is
assembled. The upper valve body portion member 102 includes a
recess 114 at the valve site and into which a portion of the
flexible sheet member 108 is drawn when the valve is operated. When
the valve is operated, a chamber 116 is formed and defined in the
area at the valve site due to the sheet member 108 being deformed
when drawn away from the nonflexing backer member 106 at the valve
site. As best seen in FIGS. 9 and 10, the nonflexing backer member
106 includes three openings or ports 126,132,138 at the valve site
(shown by the dashed line oval in FIG. 9). This valve configuration
is particularly advantageous when it is desired to converge or mix
two fluids together. For example, it may be desirable to mix fluid
entering the channel 122 with fluid entering the channel 128 and
discharging the mixed fluid through the passageway 134 when the
valve is operated. As in the case of the valves described above,
dead spots where fluid may remain after the valve operates and
closes are eliminated thus preventing any contamination during
subsequent operations. It can be seen from the valve of FIGS. 8,9
and 10 that various multiport combinations and configurations can
be realized using the valve design of the present invention. It
will also be recognized from above that one of the ports 126 or 132
can be made to function as a restrictor thus allowing fluids
entering the channel 122 to be mixed in a desired concentration
with fluid entering the channel 128.
Turning now to FIG. 11, an exemplary solenoid actuated valve site
such as might be found in a valve array such as the array
illustrated and discussed below in connection with FIG. 14 is shown
in an enlarged partial cross sectional view with the valve operated
to provide fluid communication between the two ports at the valve
site. As illustrated, a solenoid generally designated 170 is
inserted and held in an opening 172 axially with the valve site and
which opening is formed in a plastic or acrylic solenoid mounting
block 174 with the appropriate passageways for pressure or vacuum
such as the passageway in this case designated 176 and formed
therein. The block 174 is mated with a second plastic or acrylic
block 178 which has a solenoid receiving opening 180 such that when
the blocks 174 and 178 are assembled and bonded together, a single
continuous solenoid receiving cylindrical opening is defined and
formed and has a diameter dimensioned to tightly receive the
solenoid. The block 178 has a passageway or groove 182 in the
surface of the block 178 and which groove is in alignment with the
passageway 176 in the block 174 thus providing communication to the
solenoid receiving opening 180. In the embodiment illustrated, the
passageway 176 and 182 provide communication with the valve site to
apply vacuum to the thin flexible sheet member 196 to draw it away
from the two port backer surface when the solenoid 170 is operated
as will be more apparent below. The solenoid receiving opening has
a cheek or shoulder portion 184 which acts as a stop and comes into
abutting contact with the lower end portion 186 of the solenoid
170. The block 178 includes an axially aligned opening 188 through
which the end portion 190 of the plunger 192 of the solenoid 170
passes therethrough. The opening 188 is in axial alignment with the
valve site so that the plunger head 194 carried by the solenoid
plunger 192 can be moved toward and away from the thin flexible
sheet member at the valve site. When the solenoid 170 is in a
de-energized state, the spring force of the solenoid forces the
plunger 192 toward the valve site causing the plunger head 194 to
move the thin flexible sheet member 196 into contact with the
surface 198 of the non-flexing backer member 200 to seal the holes
202,204 punched therethrough and which holes are in registration
with the respective passageways 206,208 in the block 210 to block
or shut-off fluid communication between the passageways.
The solenoid 170 may be of any miniature type generally well known
including those having a threaded base however, such solenoids are
costly due to the extra machining required and a valve array or
valve site using such a solenoid requires additional precision
machining to provide a screw thread to hold the solenoid. As
explained in further detail below, applicant's invention includes a
novel method for retaining a solenoid 170 at the valve site. As
illustrated, the solenoid lower portion 212 which is received in
the solenoid receiving opening 172 includes an outer peripheral
circumferential or annular groove 214 in its surface 215. An O-ring
216 is carried by the annular groove 214 and increases the diameter
of the solenoid lower portion 212 along the annular groove. The
solenoid receiving opening 172 includes a inner peripheral surface
detent 218 positioned to receive the outer surface of the O-ring
216 when the solenoid 170 is inserted into the opening 172. The
location of the surface detent 218 as illustrated is a spherical
undercut positioned slightly toward the valve site to bias the
solenoid body towards the valve site when the solenoid is inserted.
Because the groove 218 is undercut, some axial force is required to
"snap" the solenoid into holding or retaining engagement within the
opening 172. This arrangement not only provides for a positive seat
and holding arrangement for the solenoid 170 but also allows the
solenoid to be easily removed through the application of an axial
pulling force exceeding the holding force of the O-ring against the
inner peripheral groove surface. The O-ring further functions to
provide an airtight seal so that vacuum applied at the valve site
via the passageway 176 is always present at the solenoid side of
the thin flexible sheet member 196 so that when the solenoid 170 is
actuated to retract the plunger 192 away from the valve site, the
vacuum which is present at the upper side of the flexible sheet
member 196 substantially immediately and instantaneously "pulls"
the sheet from the surface of the non-flexing backer member 200 to
allow fluid communication between the ports 202,204. In the
arrangement of the present invention, if power is lost, the
solenoid is in a fail-safe condition with the plunger 192 being
mechanically biased against the surface of the flexible sheet
member to seal the ports at the valve site.
The plunger head 194 may have a flat surface seal against the
flexible sheet member or may have a slight radius surface seal
against the flexible sheet member if a "dimple" is desired in the
flexible sheet material at the valve site. The sealing surface
material of the plunger head 194 may be rubber or other such
material which provides a "very gentle treatment" to the contact
surface of the flexible sheet member. Consequently, the flexible
sheet member receives "very gentle treatment" since the sealing
surface is against the flat Mylar surface of the non-flexing two
port backer member. The flexible sheet member can therefore be made
very thin and does not have to be "tough" as required in prior
flexible seal valves.
The volume of the valve site opening or chamber between the
flexible and non-flexing sheet members can also be adjusted as
desired by controlling the throw of the solenoid plunger to allow
the plunger head 194 to only retract a given, desired distance from
the flexible sheet member surface to create the desired volume
chamber.
Turning to FIG. 12, an alternate embodiment of a solenoid actuated
valve at a valve site similar to the valve of FIG. 11 is
illustrated therein and is generally designated 220. As
illustrated, the solenoid 220 is inserted and held in an opening
222 axially with the valve site and in the solenoid mounting block
224 with the appropriate passageways for pressure or vacuum such as
the passageway designated 226 formed therein. The block 224 is
mated with a second block 228 which has a solenoid receiving
opening 230 such that when the blocks 224 and 228 are assembled and
bonded together, a single continuous solenoid receiving cylindrical
opening is defined and formed and has a diameter dimensioned to
tightly receive the solenoid. The block 228 has a passageway 232 in
the surface of the block 228 and in communication with the
passageway 226 in the block 224 thus providing a continuous
passageway to the solenoid receiving opening 230. The passageway
226 and 232 provide communication with the valve site to apply
vacuum to the thin flexible sheet member 234 to draw it away from
the surface 236 of the two port backer member 238 when the solenoid
220 is operated. The block 228 includes an axially aligned opening
240 through which the end portion 242 of the plunger 244 of the
solenoid 220 passes therethrough. In contrast to the embodiment of
FIG. 11, the opening 240 axially aligns the plunger head 242 with
one port 246 in the two port backer member 238. Since it is only
necessary to seal one port of the two ports to shut-off
communication at the valve site, axially aligning the plunger head
to seal only one port at the valve site requires less spring force
and accordingly, the solenoid can be made smaller and consume less
energy to operate. When the solenoid 220 is in a de-energized
state, the spring force of the solenoid forces the plunger 244
toward the valve site causing the plunger head 242 to move the thin
flexible sheet member 234 into contact with the surface 236 of the
two port non-flexing backer member 238 to seal the port 246 punched
therethrough and which port is in registration with the passageway
250 in the block 252 to shut-off fluid communication between the
passageways 254 and 250.
A number of fluid analysis procedures detect the presence of ions
or other ionic mixtures of fluids passing through a given type
analysis machine, particularly medical type equipment well known to
those in the art. In such equipment it is important to insure that
the ionic mixtures are not exposed to magnetic or electrical fields
which would alter or effect the ionic mixture or its detection or
readings. Consequently, solenoid valves operated by an
electromagnet may induce electric or magnetic fields into the
mixture being analyzed thus producing incorrect results. Turning
now to FIG. 13, an alternate solenoid actuated remotely operated
valve embodying the present invention is illustrated therein and
generally designated 260. As in the valves described above
embodying the invention, the valve 260 includes a lower valve body
member 262, a non-flexing multi-port backer member 264 bonded to
the surface 266 of the lower valve body member, a thin flexible
sheet member 268 in contact with the surface 270 of the multi-port
backer member to seal the ports 272, 274 therethrough and in
registration with the groove 276 and passageway 278, respectively
in the lower valve body member 262. A solenoid plunger assembly
housing 280 defines an upper valve body member to hold the thin
flexible sheet member 268 against the surface 270 of the multiport
backer member 264. A plunger 282 is carried axially within the
housing 280 for movement toward and away from the thin flexible
sheet member. The plunger 282 has an annular flange 294 which
includes a lower flat surface 284 which presses against the
flexible sheet member to seal the ports 272, 274 due to the
downward force exerted by the plunger 282 as a result of a spring
286 circumferentially surrounding the plunger and axially aligned
within the plunger housing. The spring 286 has one end 288 held by
the inner top side 290 of the housing 280 and has its opposite end
292 resting on and pushing against the upwardly faring surface of
the flange 294 thereby urging the thin flexible sheet member
against the multiport backer member to shut-off communication
between the ports 272 and 274. The spring force need only be as
high as necessary to overcome the pressure of a fluid flowing
through the ports of the valve to shut-off the valve because
pressure, as explained below is used to dose the valve. The housing
280 includes an interior, circumferential shoulder 283 to stop or
restrict the upward travel or retraction of the plunger 282 by
contacting the flange 294 at the upper extent of the plunger
travel. The distance of the shoulder 283 above the flange 294 is
set to limit the travel of the flexible sheet member 268 to its
predetermined or desired travel. In a preferred embodiment, the
retraction is set for 0.020 inches. The housing 280 is connected to
a three way control valve represented by the block 296 via a
conduit 298 having one end 299 sealingly connected to a coupling
281 in the upper portion of the housing 280. The opposite end 297
of the conduit 298 is sealingly connected to an output 295 in the
three-way control valve 296 to form an airtight connection between
the control valve and the housing 280. The three-way control valve
296 has one input 293 connected to a source of pressure 291 and a
second input 289 connected to a source of vacuum 287. In operation,
the valve is actuated when the three-way control valve 296 diverts
vacuum from the source 287 to the interior of the housing 280 via
the conduit 298. The vacuum is adjusted to be sufficiently high to
overcome the spring force exerted on the plunger 282 to cause the
plunger to be pulled away from the valve site so that the flexible
sheet member 268 is pulled away from the backer member 264 to
provide communication between the ports 272 and 274 at the valve
site. The valve is closed or shut-off when the three-way control
valve diverts pressure from the source 291 to the interior of the
housing 280 via the conduit 298. The pressure aids in the closing
of the valve by applying pressure to the flexible sheet member 268
to substantially instantaneously close the valve. In this way, the
pressure of the spring force need only be set high enough to hold
the valve closed rather than of a force which would be needed to
close the valve. This configuration provides for a smaller diameter
valve housing since the spring geometry can be smaller because it
does not have to provide the closing force but only the holding
force.
Turning now to FIG. 14, the valve and flexible sheet member with
two port non-flexing backer member embodying the present invention
is illustrated therein and shown for illustrative purposes as it
may be utilized in a valve array with solenoid actuators and is
generally designated 300. The valve array 300 includes a number of
blocks having passageways, grooves, canals and so forth as
described in my earlier patents and which are configured to provide
the desired flow path as controlled by the valve within the flow
path. As illustrated in FIG. 14, the lower most body member 302 has
its upper face 304 in communication and contact with the lower
surface 306 of the immediately adjacent valve body portion member
308. The valve body 302 has, for illustrative purposes, passageways
310a, 310b, 310c, 310d extending through the block 302 from its
lower surface 312 through its upper surface 304 and which
passageways are used to provide fluid flow into and out of the
valve array and which passageways are further in registration with
corresponding passageways in the valve body 308 immediately above
the valve body 302. The valve body 308 has various grooves and
conduits in a desired fluid flow configuration. The lower surface
306 of the block 308 is bonded to the surface 304 of the block 302
as disclosed in the above referenced patents. The valve body 308
has its upper surface 314 in contact with the lower surface 316 of
the valve body block 318 with the appropriate passageways appearing
in the lower surface 316 of the block 318 in proper registration
with the passageways and the surface 314 of the block 308. The
block 318 is also bonded to the block 308. The non-flexing mylar
sheet or backer member 320 has holes 322,324 punched through the
backer member 320 between the upper surface 326 and lower surface
328 of the backer member 320. The holes or ports 322,324 are
located at each respective valve site and, as described above, in
registration with the respective hole, passageway, flow through or
groove in the block 318. The non-flexing mylar backer member 320 is
molecularly bonded or adhesively adhered to the upper surface 330
of the block 318. The flexible sheet member 332 has its lower face
surface 334 in facing contact with the upper surface 26 of the
nonflexing mylar backer member 320. The valve array 300 has a
solenoid holding body 338 configured with a number of openings 340
extending between the upper surface 342 and the lower face surface
344 of the block 338 each respectively arranged to hold a solenoid
assembly 346. The block 338 as illustrated has an internal canal
348 in contact with an external conduit 350 through which a vacuum
is applied as explained in further detail below. The plunger
portion or section 352 is further complementary received in a
respective opening 354 in the block 356 so that the plunger portion
of the solenoid fits into the opening 354 to allow the plunger 358
of the solenoid 346 to extend through the opening 360 in the lower
face surface 362 of the block 356. The opening 360 in the lower
face surface 362 of the block 356 is in alignment with the valve
site corresponding to the holes 322,324 in the nonflexing mylar
backer member 320. The block 356 has grooves 364 in the upper
surface 366 and interconnect each of the openings 354 at each
solenoid location. When the block 356 is bonded to the block 338, a
unitary block is formed and a vacuum applied at the inlet 350 is
distributed to each of the solenoid locations. When the valve array
is assembled, the plunger 358 of each of the respective solenoid
assemblies 346 forces the flexible mylar sheet 332 into covering
and sealing contact with the holes 322,324 in the non-flexing sheet
backer member 320 to close or block the flow passages at the valve
site. When the solenoid 346 is energized, the plunger is retracted
allowing the valve to move to its open flow position. The
application of vacuum at the valve site causes the flexible sheet
at the valve site location to be immediately withdrawn from the
surface 326 of the backer plate to provide communication between
the holes 322,324. When the solenoid is de-energized, the plunger
returns to its at rest position to force the flexible sheet member
to cover the holes 322,324 to close the valve and block fluid flow.
It can be seen that since the holes 322,324 can be located very
close to one another the valve site area can be reduced
substantially to provide a high density solenoid operated valve
array. It will also be appreciated that the solenoid valve
configuration of FIG. 12 may also be employed in the valve array of
FIG. 14 to further provide a higher density valve array.
A valve having a flexible sheet member and multi-port non-flexing
backer member has been presented above in several preferred
embodiments. It will be recognized by those skilled in the art that
numerous variations and configurations may be made to the invention
as presented and therefore the invention has been presented by way
of example rather than limitation.
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